The present invention relates to a method of manufacturing an electronic device and the electronic device, and more particularly, to a method of manufacturing an electronic device having a structure in which a substrate body and a conductive pattern formed thereon through an insulating layer are connected to each other by using a bump, and the electronic device.
For example, there has variously been provided an electronic apparatus in which an electrode and a conductive pattern are formed on a substrate body such as a semiconductor substrate. As one of types, a semiconductor device referred to as a chip size package has been provided.
The chip size package has a structure in which a rewiring (a conductive layer) is formed through an insulating layer (a protecting layer) on a surface of a semiconductor chip obtained by dicing a wafer to be a semiconductor substrate on which a device is formed.
In order to manufacture the chip size package, a plurality of electrodes is first formed on a semiconductor chip region of a semiconductor wafer and a bump is formed on each of the electrodes. The bump is formed through a bonding wire by using a bonding device.
Moreover, an insulating layer is formed on the semiconductor wafer having the bump formed thereon in order to protect a circuit surface formed on the wafer. In this case, a tip portion of the bump is formed to be exposed from the insulating layer.
Subsequently, a rewiring is formed on an upper part of the insulating layer by using a plating process or a printing process, for example. For a method of electrically bonding the rewiring to the bump, there has been employed a method of connecting the bump to the rewiring through pressure bonding or a method of connecting them by using a conductive paste as is disclosed in Patent Document 1.
Then, the wafer is divided into pieces through dicing so that a chip size package is formed.
[Patent Document 1] JP-A-2005-353913
In the method of bonding the bump to the rewiring through pressure bonding or a conductive paste, however, the electrical connection of the bump and the rewiring is not sufficient so that a connecting resistance is increased. In the case in which a semiconductor chip has a high speed, therefore, there is a possibility that an electrical characteristic might be deteriorated due to a high connecting impedance. In the method of bonding the bump to the rewiring through pressure bonding or a conductive paste, moreover, there is a problem in that a mechanical connecting property of the bump and the rewiring is not sufficient and a sufficient reliability might not be thus obtained.